COVID-19 is Observed in Older Children During the Omicron Wave in New York City

Epidemiology of Pediatric Viral Illnesses Before, During, and After the "Tripledemic" Viral Surge

OBJECTIVES

While children represented a small percentage of those hospitalized during the COVID-19 pandemic, there was a surge of pediatric viral-related admissions in the immediate postpandemic viral season. Our study compares the epidemiology and health care utilization of children with acute respiratory infections during the 2022-2023 season to prepandemic and subsequent postpandemic seasons to see if trends persisted.

METHODS

We examined administrative data for children who presented to 2 urban pediatric emergency departments (ED) during 3 periods: 2017-2020 (prepandemic), 2022-2023 (immediate postpandemic), and 2023-2024 (subsequent postpandemic). Outcomes included hospitalization rate for viral-related indications, stepdown/intensive care unit (ICU) admission, and use of advanced respiratory support. Multivariable regression controlled for demographics and specific viruses.

RESULTS

During the study period, there were 65,313 all-cause ED encounters. Compared with prepandemic seasons, viral-related admissions doubled in 2022-2023. In addition to an increase in ED visits, the odds of viral-related admission increased by 98% [adjusted odds ratio (aOR): 1.98; 99.8% CI: 1.75-2.24], odds of stepdown/ICU admission increased by 131% (aOR: 1.31; 99.8% CI: 1.67-3.21) and odds of advanced respiratory support increased by 70% (aOR: 1.70; 99.8% CI: 1.21-2.40). In 2023-2024, the stepdown/ICU admission rate remained the same compared with 2022-2023, and the odds of advanced respiratory support increased (aOR: 1.79, 99.8% CI: 1.22-2.63). Infection with respiratory syncytial virus increased adjusted odds of more advanced care.

CONCLUSIONS

Pediatric ED visits and hospitalization rate decreased in 2023-2024 compared with the postpandemic surge, but the admission rate remained high compared with prepandemic seasons, percent admitted to stepdown/ICU persisted, and the use of advanced respiratory support continued to increase.

Comparative analysis of croup severity and treatment in pediatric patient: a study of COVID-19 positive vs. negative cases during peak Omicron

BACKGROUND

The Omicron variant of SARS-CoV-2 has been associated with unique clinical presentations in children, including croup-like symptoms such as barking cough, hoarseness, and respiratory distress. This study aimed to compare the clinical, laboratory, and treatment characteristics of hospitalized pediatric patients with croup who tested positive or negative for COVID-19 during the Omicron wave.

METHODS

A retrospective, descriptive-analytical study was conducted on 111 pediatric patients hospitalized with croup at Bahrami Children's Hospital and the Children's Medical Center in Iran from January 21 to March 20, 2022. Patients were categorized into two groups: PCR-positive (Omicron group, n = 30) and PCR-negative (non-Omicron group, n = 81). Data on demographics, clinical severity, laboratory indices, treatments, and outcomes were extracted and analyzed using SPSS version 20.

RESULTS

The mean age of the Omicron group was significantly younger (16.93 ± 24.80 months) compared to the non-Omicron group (32.58 ± 37.26 months; p = 0.049). Symptom severity was higher in the Omicron group, with moderate to severe symptoms observed in 73.4% of patients, compared to 32.1% in the non-Omicron group (p = 0.001). The Omicron group had longer hospital stays (2.59 ± 3.93 vs. 2.11 ± 2.75 days; p = 0.016) and required more nebulized epinephrine (2.47 ± 1.27 vs. 1.77 ± 1.003 days; p = 0.003) and repeat corticosteroid doses (83.3% vs. 38.3%; p = 0.0001). Laboratory findings showed no significant differences between the groups (all p > 0.05).

CONCLUSION

Children with croup during the Omicron surge exhibited increased symptom severity, required more intensive treatment, and experienced longer hospital stays compared to those without COVID-19. These findings emphasize the need for heightened clinical awareness and tailored management strategies for Omicron-related croup in pediatric populations.

Co-detection of various viruses in SARS-CoV-2 in children with respiratory infections

The co-detection of SARS-CoV-2 variant with other respiratory virus has been extensively investigated. However, conclusive evidence remains elusive and conflicted. This study investigated the source- and age-dependent prevalence, incidence, and co-detection of multiple viral infections in children younger than 18 years old who presented with clinical symptoms indicative of respiratory infections during SARS-CoV-2 pandemic. We retrospectively obtained and analyzed pediatric patients admitted to the institution and underwent Film Array Respiratory Panel (BIOFIRE® RP2.1) testing between January 2021 and December 2022. This encompassed pre-Delta, Delta and omicron periods, evaluating Film Array results for singular and co-detections. The overall detection rate was 84.2% (1670/1983) among 1,983 pediatric patients. Of these, 106 were SARS-CoV-2 positive. Notably, 45 patients (42%) harbored SARS-CoV-2 as the sole pathogen. Co-detection was significant; 32 cases (30.2%) involved Human Rhinovirus/Enterovirus, 29 (24.5%) involved parainfluenza 3, and 26 (24.5%) involved Respiratory syncytial virus. Peaks of co-detected parainfluenza 3 and Respiratory syncytial virus were evident in the winter of 2022 and absent in 2021. The top three viral strain for co-detection was HRV/EV, PIV-3, and RSV. The emergence order of co-detection strain was HRV/EV ◊PIV-3◊ RSV during the Omicron period in Taiwan. We identified characteristic patterns of SARS-CoV-2-associated co-detections, with a notable emphasis on the co-detection of HRV/EV, PIV3, and RSV alongside SARS-CoV-2. This association appears to hold heightened significance during the Omicron variant era compared to earlier SARS-CoV-2 variants, which contrast with previous studies. The simultaneous circulation of different variants may contribute to variations in viral co-detection, particularly in young children, warranting further investigation.

Natural immunity and protection against variants in South African children through five COVID-19 waves: A prospective study

OBJECTIVES

Children have been largely spared from serious disease through the COVID-19 pandemic despite a high exposure to SARS-CoV-2. Antibody responses to exposure and their role in protecting children from subsequent variant infection remain poorly understood.

METHODS

This is a prospective cohort study of children in a South African community through ancestral/Beta/Delta/Omicron BA.1/BA.2 and BA.4/BA.5 SARS-CoV-2 waves (March 2020-October 2022). Health seeking behavior/illness was recorded and postwave serum samples measured for immunoglobulin (Ig) G to spike (S) (CoV2-S-IgG) by electrochemiluminescent immunosorbent assay. To estimate the protective CoV2-S-IgG threshold levels, logistic functions were fit to describe the correlation of CoV2-S-IgG measured before a wave and the probability for seroconversion/boosting thereafter.

RESULTS

Despite little disease, 125 per 366 (34.2%) children (median age 6.7 years [interquartile range 5.99-7.4 years]) were seropositive after wave I, rising to 53.6%, 76.0%, and 96.2% and 99.2% after waves II (Beta), III (Delta), and IV and V (Omicron variants), respectively. CoV2-S-IgG induced by natural exposure protected against subsequent SARS-CoV-2 infection, with the greatest protection for Beta and least for Omicron. The levels of IgG specific for ancestral S antigen that provided a 50% protective threshold for the subsequent wave were lowest for the Beta and highest for the Omicron BA.1/BA.2 wave. In the multivariate analysis, maternal seropositivity (adjusted odds ratio = 2.57 [95% confidence interval: 1.72-3.82]) was strongly associated with child seropositivity.

CONCLUSION

Children responded robustly to successive waves of SARS-CoV-2, mounting IgG responses to S antigen that were protective against subsequent waves. In the absence of vaccination, almost all children were seropositive after wave V but none were hospitalized, suggesting that natural immunity alone may be sufficient to protect children in a pandemic setting.

The changing clinical presentation of COVID-19 in children during the course of the pandemic

AIM

To investigate the evolution of clinical symptoms of COVID-19 in children throughout the pandemic.

METHODS

In this national prospective surveillance study, symptoms in children hospitalised with COVID-19 were collected from all paediatric hospitals in Switzerland between March 2020 and March 2023. Data was analysed across four time periods, according to the predominantly circulating SARS-CoV-2 variant: T1 (wild-type), T2 (Alpha), T3 (Delta) and T4 (Omicron), as well as by age group.

RESULTS

The study included 1323 children. The proportion of children admitted to an intensive care unit remained stable throughout the pandemic. However, the pattern and frequency of clinical manifestations changed over time. Respiratory symptoms were less prevalent during T1 (wild-type), fever during T2 (Alpha) and rash during T4 (Omicron). In contrast, fever and neurological symptoms were more prevalent during T4 (Omicron). Newly described symptoms during T4 (Omicron) included conjunctivitis, laryngotracheitis and seizures. Fever was more prevalent among neonates and infants whereas respiratory symptoms were more common among infants. Gastrointestinal symptoms were more frequent among toddlers, while both toddlers and school-aged children presented with neurological symptoms more often than other age groups.

CONCLUSION

Continuous surveillance is required to detect changes in manifestations and there by be prepared for the optimal management of complications in children with COVID-19.

Differences in the Clinical Manifestations and Host Immune Responses to SARS-CoV-2 Variants in Children Compared to Adults

The COVID-19 pandemic challenged the medical field to rapidly identify and implement new approaches to the diagnosis, treatment and prevention of SARS-CoV-2 infections. The scientific community also needed to rapidly initiate basic, translational, clinical and epidemiological studies to understand the pathophysiology of this new family of viruses, which continues to evolve with the emergence of new genetic variants. One of the earliest clinical observations that provided a framework for the research was the finding that, in contrast to most other respiratory viruses, children developed less severe acute and post-acute disease compared to adults. Although the clinical manifestations of SARS-CoV-2 infection changed with each new wave of the pandemic, which was dominated by evolving viral variants, the differences in severity between children and adults persisted. Comparative immunologic studies have shown that children mount a more vigorous local innate response characterized by the activation of interferon pathways and recruitment of innate cells to the mucosa, which may mitigate against the hyperinflammatory adaptive response and systemic cytokine release that likely contributed to more severe outcomes including acute respiratory distress syndrome in adults. In this review, the clinical manifestations and immunologic responses in children during the different waves of COVID-19 are discussed.

Clinical Features and Outcomes of Omicron-Associated Croup in Children

Objective: This study was aimed to describe the clinical features and outcomes of Omicron-associated croup in children. Methods: A total of 105 children aged 3-60 months (median age 11 months) with coronavirus disease 2019 (COVID-19) and cough were admitted to our hospital from December 16, 2022, to December 31, 2022. Their clinical features, treatment, and outcomes were reviewed. These children were followed up for 8 months. Results: Among the cases, 5 had complex medical histories, while the other children were generally healthy. Out of the cases, 41 (38.3%), 57 (54.4%), and 7 (6.7%) had mild, moderate, and severe laryngeal obstruction, respectively. They developed croup after 1-5 days of fever (median 2 days). The majority (90.5%) of COVID-19 children with croup did not have pneumonia, and most of them (64.8%) had decreased eosinophil counts. Additionally, most other blood routine indicators were normal. Five other viral infections (chlamydia pneumoniae, respiratory syncytial virus, adenovirus, coxsackie virus, and mycoplasma pneumoniae) were tested in 51 cases, and all results were negative. All cases recovered from croup after receiving prompt nebulization therapy and/or intravenous drip of hormone. The hospitalization rate was 6.7%. During the 8-month follow-up period, 71 cases experienced repeated fever due to various infections, but only 4 cases (4/105, 3.8%) had repeated croup. Conclusion: Omicron is a risk factor for croup, with most cases presenting mild to moderate laryngeal obstructions. Co-viral infection testing is unnecessary for such cases. The symptoms of Omicron-associated croup may be more severe than croup associated with other viruses; however, unnecessary hospitalizations can be avoided, leading to reduced healthcare expenses.